2 * Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
3 * Author: Brendan Le Foll <brendan.le.foll@intel.com>
4 * Copyright (c) 2014 Intel Corporation.
6 * Permission is hereby granted, free of charge, to any person obtaining
7 * a copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sublicense, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice shall be
15 * included in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 #include "mraa_internal.h"
38 #define SYSFS_CLASS_GPIO "/sys/class/gpio"
43 mraa_gpio_get_valfp(mraa_gpio_context dev)
46 sprintf(bu, SYSFS_CLASS_GPIO "/gpio%d/value", dev->pin);
47 dev->value_fp = open(bu, O_RDWR);
48 if (dev->value_fp == -1) {
49 return MRAA_ERROR_INVALID_RESOURCE;
56 mraa_gpio_init(int pin)
59 syslog(LOG_ERR, "gpio: platform not initialised");
62 if (pin < 0 || pin > plat->phy_pin_count) {
63 syslog(LOG_ERR, "gpio: pin %i beyond platform definition", pin);
66 if (plat->pins[pin].capabilites.gpio != 1) {
67 syslog(LOG_ERR, "gpio: pin %i not capable of gpio", pin);
70 if (plat->pins[pin].gpio.mux_total > 0) {
71 if (mraa_setup_mux_mapped(plat->pins[pin].gpio) != MRAA_SUCCESS) {
72 syslog(LOG_ERR, "gpio: unable to setup muxes");
77 mraa_gpio_context r = mraa_gpio_init_raw(plat->pins[pin].gpio.pinmap);
80 if (advance_func->gpio_init_post != NULL) {
81 mraa_result_t ret = advance_func->gpio_init_post(r);
82 if (ret != MRAA_SUCCESS) {
91 mraa_gpio_init_raw(int pin)
93 if (advance_func->gpio_init_pre != NULL) {
94 if (advance_func->gpio_init_pre(pin) != MRAA_SUCCESS)
104 mraa_gpio_context dev = (mraa_gpio_context) malloc(sizeof(struct _gpio));
106 syslog(LOG_CRIT, "gpio: Failed to allocate memory for context");
110 memset(dev, 0, sizeof(struct _gpio));
112 dev->isr_value_fp = -1;
116 char directory[MAX_SIZE];
117 snprintf(directory, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/", dev->pin);
119 if (stat(directory, &dir) == 0 && S_ISDIR(dir.st_mode)) {
120 dev->owner = 0; // Not Owner
122 int export = open(SYSFS_CLASS_GPIO "/export", O_WRONLY);
124 syslog(LOG_ERR, "gpio: Failed to open export for writing");
128 length = snprintf(bu, sizeof(bu), "%d", dev->pin);
129 if (write(export, bu, length*sizeof(char)) == -1) {
130 syslog(LOG_ERR, "gpio: Failed to write to export");
142 mraa_gpio_write_register(mraa_gpio_context dev,int value)
144 if (advance_func->gpio_mmaped_write_replace != NULL)
145 return advance_func->gpio_mmaped_write_replace(dev,value);
146 if (advance_func->gpio_mmaped_write_pre != NULL) {
147 mraa_result_t pre_ret = (advance_func->gpio_mmaped_write_pre(dev,value));
148 if(pre_ret != MRAA_SUCCESS)
152 *((unsigned *)dev->reg) |= (1<<dev->reg_bit_pos);
155 *((unsigned *)dev->reg) &= ~(1<<dev->reg_bit_pos);
157 if (advance_func->gpio_mmaped_write_post != NULL)
158 return advance_func->gpio_mmaped_write_post(dev,value);
163 mraa_gpio_wait_interrupt(int fd)
168 // setup poll on POLLPRI
170 pfd.events = POLLPRI;
172 // do an initial read to clear interupt
176 return MRAA_ERROR_INVALID_RESOURCE;
179 // Wait for it forever or until pthread_cancel
180 // poll is a cancelable point like sleep()
181 int x = poll (&pfd, 1, -1);
183 // do a final read to clear interupt
190 mraa_gpio_interrupt_handler(void* arg)
192 mraa_gpio_context dev = (mraa_gpio_context) arg;
195 // open gpio value with open(3)
197 sprintf(bu, SYSFS_CLASS_GPIO "/gpio%d/value", dev->pin);
198 dev->isr_value_fp = open(bu, O_RDONLY);
201 ret = mraa_gpio_wait_interrupt(dev->isr_value_fp);
202 if (ret == MRAA_SUCCESS) {
203 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
205 // In order to call a python object (all python functions are objects) we
206 // need to aquire the GIL (Global Interpreter Lock). This may not always be
207 // nessecary but especially if doing IO (like print()) python will segfault
208 // if we do not hold a lock on the GIL
209 PyGILState_STATE gilstate = PyGILState_Ensure();
212 arglist = Py_BuildValue("(i)", dev->isr_args);
213 if (arglist == NULL) {
214 syslog(LOG_ERR, "gpio: Py_BuildValue NULL");
216 ret = PyEval_CallObject((PyObject*)dev->isr, arglist);
218 syslog(LOG_ERR, "gpio: PyEval_CallObject failed");
225 PyGILState_Release (gilstate);
227 dev->isr(dev->isr_args);
229 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
231 // we must have got an error code so die nicely
232 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
233 close(dev->isr_value_fp);
234 dev->isr_value_fp = -1;
241 mraa_gpio_edge_mode(mraa_gpio_context dev, gpio_edge_t mode)
243 if (dev->value_fp != -1) {
244 close(dev->value_fp);
248 char filepath[MAX_SIZE];
249 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/edge", dev->pin);
251 int edge = open(filepath, O_RDWR);
253 syslog(LOG_ERR, "gpio: Failed to open edge for writing");
254 return MRAA_ERROR_INVALID_RESOURCE;
260 case MRAA_GPIO_EDGE_NONE:
261 length = snprintf(bu, sizeof(bu), "none");
263 case MRAA_GPIO_EDGE_BOTH:
264 length = snprintf(bu, sizeof(bu), "both");
266 case MRAA_GPIO_EDGE_RISING:
267 length = snprintf(bu, sizeof(bu), "rising");
269 case MRAA_GPIO_EDGE_FALLING:
270 length = snprintf(bu, sizeof(bu), "falling");
274 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
276 if (write(edge, bu, length*sizeof(char)) == -1) {
277 syslog(LOG_ERR, "gpio: Failed to write to edge");
279 return MRAA_ERROR_INVALID_RESOURCE;
287 mraa_gpio_isr(mraa_gpio_context dev, gpio_edge_t mode, void (*fptr)(void *), void * args)
289 // we only allow one isr per mraa_gpio_context
290 if (dev->thread_id != 0) {
291 return MRAA_ERROR_NO_RESOURCES;
294 if (MRAA_SUCCESS != mraa_gpio_edge_mode(dev, mode)) {
295 return MRAA_ERROR_UNSPECIFIED;
299 dev->isr_args = args;
300 pthread_create (&dev->thread_id, NULL, mraa_gpio_interrupt_handler, (void *) dev);
306 mraa_gpio_isr_exit(mraa_gpio_context dev)
308 mraa_result_t ret = MRAA_SUCCESS;
310 // wasting our time, there is no isr to exit from
311 if (dev->thread_id == 0 && dev->isr_value_fp == -1) {
315 // stop isr being useful
316 ret = mraa_gpio_edge_mode(dev, MRAA_GPIO_EDGE_NONE);
318 if ((dev->thread_id != 0)) {
319 if ((pthread_cancel(dev->thread_id) != 0) || (pthread_join(dev->thread_id, NULL) != 0)) {
320 ret = MRAA_ERROR_INVALID_HANDLE;
324 // close the filehandle in case it's still open
325 if (dev->isr_value_fp != -1) {
326 if (close(dev->isr_value_fp) != 0) {
327 ret = MRAA_ERROR_INVALID_PARAMETER;
332 // Dereference our Python call back function
336 // assume our thread will exit either way we just lost it's handle
338 dev->isr_value_fp = -1;
343 mraa_gpio_mode(mraa_gpio_context dev, gpio_mode_t mode)
345 if (advance_func->gpio_mode_replace != NULL)
346 return advance_func->gpio_mode_replace(dev,mode);
348 if (advance_func->gpio_mode_pre != NULL) {
349 mraa_result_t pre_ret = (advance_func->gpio_mode_pre(dev,mode));
350 if(pre_ret != MRAA_SUCCESS)
354 if (dev->value_fp != -1) {
355 close(dev->value_fp);
359 char filepath[MAX_SIZE];
360 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/drive", dev->pin);
362 int drive = open(filepath, O_WRONLY);
364 syslog(LOG_ERR, "gpio: Failed to open drive for writing");
365 return MRAA_ERROR_INVALID_RESOURCE;
371 case MRAA_GPIO_STRONG:
372 length = snprintf(bu, sizeof(bu), "strong");
374 case MRAA_GPIO_PULLUP:
375 length = snprintf(bu, sizeof(bu), "pullup");
377 case MRAA_GPIO_PULLDOWN:
378 length = snprintf(bu, sizeof(bu), "pulldown");
381 length = snprintf(bu, sizeof(bu), "hiz");
385 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
387 if (write(drive, bu, length*sizeof(char)) == -1) {
388 syslog(LOG_ERR, "gpio: Failed to write to drive mode");
390 return MRAA_ERROR_INVALID_RESOURCE;
395 if (advance_func->gpio_mode_post != NULL)
396 return advance_func->gpio_mode_post(dev,mode);
401 mraa_gpio_dir(mraa_gpio_context dev, gpio_dir_t dir)
403 if (advance_func->gpio_dir_replace != NULL)
404 return advance_func->gpio_dir_replace(dev,dir);
405 if (advance_func->gpio_dir_pre != NULL) {
406 mraa_result_t pre_ret = (advance_func->gpio_dir_pre(dev,dir));
407 if(pre_ret != MRAA_SUCCESS)
412 return MRAA_ERROR_INVALID_HANDLE;
414 if (dev->value_fp != -1) {
415 close(dev->value_fp);
418 char filepath[MAX_SIZE];
419 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/direction", dev->pin);
421 int direction = open(filepath, O_RDWR);
423 if (direction == -1) {
424 return MRAA_ERROR_INVALID_RESOURCE;
431 length = snprintf(bu, sizeof(bu), "out");
434 length = snprintf(bu, sizeof(bu), "in");
438 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
441 if (write(direction, bu, length*sizeof(char)) == -1) {
443 return MRAA_ERROR_INVALID_RESOURCE;
447 if (advance_func->gpio_dir_post != NULL)
448 return advance_func->gpio_dir_post(dev,dir);
453 mraa_gpio_read(mraa_gpio_context dev)
458 if (dev->value_fp == -1) {
459 if (mraa_gpio_get_valfp(dev) != MRAA_SUCCESS) {
460 syslog(LOG_ERR, "gpio: Failed to get value file pointer");
464 // if value_fp is new this is pointless
465 lseek(dev->value_fp, 0, SEEK_SET);
468 if (read(dev->value_fp, bu, 2*sizeof(char)) != 2) {
469 syslog(LOG_ERR, "gpio: Failed to read a sensible value from sysfs");
472 lseek(dev->value_fp, 0, SEEK_SET);
474 return strtol(bu, NULL, 10);
478 mraa_gpio_write(mraa_gpio_context dev, int value)
481 return MRAA_ERROR_INVALID_HANDLE;
484 return mraa_gpio_write_register(dev,value);
486 if (advance_func->gpio_write_pre != NULL) {
487 mraa_result_t pre_ret = (advance_func->gpio_write_pre(dev,value));
488 if(pre_ret != MRAA_SUCCESS)
492 if (dev->value_fp == -1) {
493 mraa_gpio_get_valfp(dev);
495 if (lseek(dev->value_fp, 0, SEEK_SET) == -1) {
496 return MRAA_ERROR_INVALID_RESOURCE;
500 int length = snprintf(bu, sizeof(bu), "%d", value);
501 if (write(dev->value_fp, bu, length*sizeof(char)) == -1) {
502 return MRAA_ERROR_INVALID_HANDLE;
505 if (advance_func->gpio_write_post != NULL)
506 return advance_func->gpio_write_post(dev,value);
511 mraa_gpio_unexport_force(mraa_gpio_context dev)
513 int unexport = open(SYSFS_CLASS_GPIO "/unexport", O_WRONLY);
514 if (unexport == -1) {
515 syslog(LOG_ERR, "gpio: Failed to open unexport for writing");
516 return MRAA_ERROR_INVALID_RESOURCE;
520 int length = snprintf(bu, sizeof(bu), "%d", dev->pin);
521 if (write(unexport, bu, length*sizeof(char)) == -1) {
522 syslog(LOG_ERR, "gpio: Failed to write to unexport");
524 return MRAA_ERROR_INVALID_RESOURCE;
528 mraa_gpio_isr_exit(dev);
532 mraa_gpio_unexport(mraa_gpio_context dev)
535 return mraa_gpio_unexport_force(dev);
537 return MRAA_ERROR_INVALID_RESOURCE;
541 mraa_gpio_close(mraa_gpio_context dev)
543 if (dev->value_fp != -1) {
544 close(dev->value_fp);
546 mraa_gpio_unexport(dev);
552 mraa_gpio_owner(mraa_gpio_context dev, mraa_boolean_t own)
555 return MRAA_ERROR_INVALID_RESOURCE;
561 mraa_gpio_use_mmaped(mraa_gpio_context dev, mraa_boolean_t mmap_en)
564 return MRAA_ERROR_INVALID_RESOURCE;
567 if (mraa_pin_mode_test(dev->phy_pin, MRAA_PIN_FAST_GPIO) == 0)
568 return MRAA_ERROR_NO_RESOURCES;
570 mraa_mmap_pin_t *mmp = mraa_setup_mmap_gpio(dev->phy_pin);
572 return MRAA_ERROR_INVALID_RESOURCE;
575 if (dev->mmap == 0) {
576 close(dev->value_fp);
578 fd = open(mmp->mem_dev, O_RDWR);
580 syslog(LOG_ERR, "gpio: Unable to open memory device");
582 return MRAA_ERROR_INVALID_RESOURCE;
584 dev->reg_sz = mmp->mem_sz;
585 dev->reg = mmap(NULL, dev->reg_sz, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
586 dev->reg_bit_pos = mmp->bit_pos;
591 return MRAA_ERROR_INVALID_PARAMETER;
595 if (dev ->mmap == 1) {
596 munmap(dev->reg, dev->reg_sz);
599 return MRAA_ERROR_INVALID_PARAMETER;